<?php
class A {
	
	private $a = 10;
	
	public function __get( $var ) {
		return $this->$var;
	}
}

class B extends A {
	
	public function getAValue() {
		return $this->a;
	}
}

class C extends B {
	
	private $a = 20;
	
	public function __get( $var ) {
		return $this->$var;
	}
}

class D extends C {
	
}

$a = new D();
echo $a->getAValue(); // What will be printed???
?>